| Osterferien | Easter holidays |
| Osterfeuer | Easter fire |
| Osterkerze | Paschal candle |
| Sommerferien | summer holidays summer vacation |
| Ostlerin | Oriental |
| Ostelbien | East Elbia |
| Osteopenie | osteopenia |
| Osterei | Easter egg |
| Osterfest | Easter |
| Osterspiel | Easter drama |
| Osterzeit | Easter |
| Ostrumelien | Eastern Rumelia |
| Österreich | Austria |
| Interferon | interferon |
| interferieren | interfere |
| Interferenz | interference |
| Interserie | Interserie |
| alterieren | upset alter inflect |
| iterieren | iterate |
| unterwerfen | subdue |